The present invention relates to a smartcatd for use with a receiver of encrypted broadcast signals in a broadcast and reception system, a receiver/decoder for receiving and decrypting broadcast signals, apparatus for broadcasting encrypted signals and a method of broadcasting encrypted signals.
In particular, but not exclusively, the invention relates to a mass-market broadcast system having some or all of the following preferred features:
It is an information broadcast system, preferably a radio and/or television broadcast system
It is a satellite system (although it could be applicable to cable or terrestrial transmission)
It is a digital system, preferably using the MPEG, more preferably the MPEG-2, compression system for data/signal transmission
It affords the possibility of interactivity
It uses smartcards.
The term xe2x80x9csmartcardxe2x80x9d is used herein with a broad meaning, and includes (but not exclusively so) any microprocessor based card or object of similar function and preformance.
In a first aspect, the present invention provides a smartcard for use with a receiver of encrypted broadcast signals, the smartcard comprising:
a microprocessor for enabling or controlling decryption of said signals; and a memory coupled to said microprocessor; said microprocessor being adapted to enable or control the individual decryption of a plurality of such signals from respective broadcast suppliers of such signals by means of respective dynamically created zones in said memory, said dynamically created zones each being arranged to store decryption data associated with a respective one of said broadcast suppliers. Dynamic creation (and removal) of zones in the smartcard allows for the rights afforded to the subscriber by means of the smartcard to be changed easily and quickly by, for example, EMMs (Entitlement Management Messages) which are periodically transmitted by the broadcaster, received by the receiver/decoder and passed to the smartcard.
Preferably, the smartcard further comprises an identifier and at least one secret decryption key associated with a respective one of said broadcast suppliers, said identifier and the or each key being stored in one of said dynamically created zones and being arranged to decrypt broadcast signals having an identity corresponding to that identifier and encrypted using an encryption key corresponding to that decryption key.
The smartcard may further comprise for each zone stored group identifier and a further identifier which identifies it within that group and is arranged to decrypt broadcast signals having an identity corresponding to the stored group identifier.
The smartcard may be arranged to maintain a first series of memory zones containing the identities of the respective broadcast suppliers and a second series of dynamically created memory zones, the memory zones in the second series each being labelled with the identity of a broadcast supplier and containing data including said decryption data used for the handling of received broadcast signals from that supplier, a plurality of memory zones in the second series having a common identity label and containing different classes of data relating to the handling of received broadcast signals from that broadcast supplier.
Preferably, the smartcard is arranged to create dynamically the memory zones of said first series. The dynamically created memory zones may be continuous.
Preferably, the smartcard comprises a management memory zone arranged to store data for controlling the dynamic creation of said dynamically created zones.
One of said dynamically created zones may contain rights data indicating a particular selection of broadcast items broadcast by a broadcast supplier, which the user of the smartcard is entitled to decrypt, the smartcard being arranged to utilise said rights data to decrypt items broadcast by that supplier.
A transaction memory zone may be defined in the smartcard in addition to said dynamically created zones and which contains further rights data concerning items broadcast by a broadcast supplier which a user of the smartcard is entitled to decrypt only in response to a transaction output signal which can be generated by the smartcard under the control of the user.
The smartcard may further comprise a counter for counting the number of occasions on which an item is broadcast following the output of a said transaction output signal, the smartcard being arranged to gate the decryption of that item in dependence upon the count value reached by said counter.
A second aspect of the present invention provides a receiver/decoder for use with a smartcard as described above, the receiver/decoder comprising a smartcard reader and being arranged to decrypt broadcast encrypted signals under the control of the subscriber smartcard.
The receiver/decoder may be arranged to decrypt encrypted broadcast video and/or audio signals and to generate corresponding video and/or audio output.
Preferably, the receiver/decoder has a relatively high bandwidth input port for receiving said encrypted broadcast signals and a relatively low bandwidth output port arranged to transmit output control signals back to a broadcast transmitter.
Preferably the receiver/decoder contains a stored identifier and is arranged to work only with a smartcard having a corresponding stored identifier.
In a third aspect, the present invention provides apparatus for broadcasting encrypted signals to receiver/decoders, the apparatus comprising means for generating two of more classes of broadcast control signals, wherein each class of such control signals includes receiver/decoder ID data for selectively enabling receiver/decoders having a corresponding ID to respond to such a class of control signals, said receiver/decoder ID data including group ID data for enabling one or more groups of receiver/decoders all to respond to a common class of such control signals, the apparatus being provided with database means which is arranged to distribute dynamically individual receiver/decoders between different ID groups in response to input information.
The database means may be responsive to signals received from the receiver/decoders to change the distribution of receiver/decoders between groups.
The apparatus may be arranged to broadcast control signals for changing the distribution of receiver/decoders between groups in response to said input information.
Different classes of control signals may enable the decryption of different parts of a broadcast encrypted data stream.
Preferably, the input information includes payment information. The classes of control signals may include classes which control subscription to decrypt encrypted broadcast signals from different broadcast suppliers. The classes of control signals may also include classes which control purchase of the right to decrypt broadcast encrypted data signals in different time frames.
Preferably, the encrypted broadcast signals are video and/or audio signals, and the apparatus may be arranged to transmit said encrypted data signals to a satellite in orbit.
Each group may comprise up to 256 members.
In a fourth aspect, the present invention provides a receiver/decoder for receiving encrypted broadcast signals, the receiver/decoder comprising a group ID and being responsive to a class of broadcast control signals having a corresponding ID to said group ID, the receiver/decoder being arranged to change its group ID in response to a further control signal.
Further control signal may comprise a broadcast signal, said broadcast signal and said encrypted broadcast signals being arranged to be received by said receiver/decoder.
Preferably, the group ID is recorded in a smartcard removably inserted in the receiver/decoder. The encrypted broadcast signals may be video and/or audio signals.
In a fifth aspect the present invention provides a system for broadcasting and receiving digital data signals comprising apparatus as described above in conjunction with a receiver/decoder as described above.
In a sixth aspect, the present invention provides a method of broadcasting encrypted signals to receiver/decoders, the method comprising generating two or more classes of broadcast control signals, each class of such signals including receiver/decoder ID data for selectively enabling receivers/decoders having a corresponding ID to respond to such a class of control signals, and distributing dynamically individual receiver/decoders between different ID groups in response to input information.
The input information preferably includes payment information and said classes of control signals enable the receiver/decoders to selectively decrypt portions of an encrypted broadcast video and/or audio stream.
In a seventh aspect, the present invention provides apparatus for broadcasting encrypted signals to receiver/decoders, the apparatus comprising means for generating control signals for controlling or enabling the decryption of said encrypted signals, means for associating control signals with respective program transmissions within said broadcast signals, the associating means comprising means for generating a signal identifying each transmission in a series of transmissions of the same program.
Preferably, the apparatus further comprises means for generating a signal for setting a limit at the receiver/decoders on the number of transmissions in said series which can be decrypted. The apparatus may be responsive to an input signal from a receiver/decoder to vary said limit.
Preferably, the apparatus is arranged to transmit said Video and/or audio stream to a satellite in orbit.
In an eighth aspect, the present invention provides a receiver/decoder for receiving and decrypting broadcast signals in a Pay Per View (PPV) mode, the receiver/decoder comprising means for detecting control signals which enable or control the decryption of particular program transmissions within said broadcast signals, said control signals including information identifying each transmission in a series of transmissions of the same program, and limiting means coupled to said detecting means for limiting the number of transmissions in said series which can be decrypted.
Preferably, the limiting means comprises a counter arranged to be incremented or decremented towards a stored limit value in response to each successive viewing of a transmission within said series. The receiver/decoder preferably comprises means for adjusting said limit value in response to a received broadcast signal. Preferably, the limiting means comprises a smartcard removably inserted in the receiver/decoder.
In a ninth aspect, the present invention provides a receiver/decoder for receiving and decrypting encrypted broadcast signals, the receiver/decoder comprising:
a smartcard reader;
a processor coupled to the smarteard reader and arranged to decrypt said signals in dependence upon an output from the smartcard reader;
memory means containing a stored ID of the receiver/decoder;
means for comparing said stored ID with an ID of a smartcard read by the smartcard reader; and
means for enabling or disabling the decryption of said signals in dependence upon the comparison.
The enabling means may be arranged to enable or disable said smartcard.
The processor may be arranged to enable said smartcard in response to a handshake routine between the receiver/decoder and smartcard.
The receiver/decoder may be arranged to receive and decrypt broadcast video and/or audio signals.
In a tenth aspect, the present invention provides a smartcard for use in a recciver/decoder as described above, said smartcard including a memory containing a list of IDs of respective receiver/decoders with which it may operate and indications as to whether the smartcard may operate with each of said listed receiver/decoders
In an eleventh aspect, the present invention provide a combination of a receiver/decoder as described above and a smartcard as described above, said receiver/decoder further comprising means for reading the ID of each receiver/decoder listed in the memory of said smartcard and the indication associated therewith to determine whether the smartcard may be used with the receiver/decoder.
In a twelfth aspect, the present invention provides a smartcard for use with a receiver of encrypted broadcast signals, the smartcard comprising
a microprocessor for enabling or controlling decryption of said signals; and
a memory coupled to said microprocessor;
said microprocessor being adapted to enable or control the individual decryption of a plurality of such signals from respective broadcast suppliers of such signals by means of respective zones in said memory, said zones each being arranged to store decryption data associated with a respective one of said broadcast suppliers, said decryption data including a priority level assigned to the smartcard by the respective broadcast supplier and enabling the decryption of signals associated with that priority level broadcast by that broadcast supplier.
The priority level may be assigned to the smartcard by means of a control signal broadcast by the broadcast supplier.
In a thirteenth aspect, the present invention provides apparatus for broadcasting encrypted broadcast signals to receiver/decoders, said receiver/decoders having assigned thereto a respective priority level, the apparatus comprising:
means for generating control signals for controlling or enabling the decryption of said broadcast signals, the control signals each having an address portion for selectively enabling decryption by a receiver/decoder having a corresponding address; and
means for addressing receiver/decoders with said control signals selectively according to their respective priority levels.
The apparatus may further comprise means for generating a first set of control signals associated with a respective broadcast supplier of broadcast signals and a second set of control signals associated with respective programs, the control signals in the second set having a switching portion arranged to gate decryption by said receiver/decoders, the control signals in said second set having said address portion.
The apparatus may be arranged to black out decryption of a selected program in a selected geographical location.